This allows supervisor to send a warm shutdown to celery and wait for
celery to complete tasks and clean up before shutting down.

Remove config related to the CDN Experiments.

remove NewRelic from role

Initial support for journals service

TE-2597 Uninstall JobConfigHistory, upgrade GHPRB

Copy/pasta added half of the CSRF cookie

Also make session cookie overridable while here, for future use.

Allow us to set a custom cloudwatch dictionary for the metrics

OPS-2998

TE-2560 Add Warnings plugin to build Jenkins

* Remove newrelic server as it is no longer supported.

If you try to start it, it connects to Newrelic and then fails to start.

```
2018-06-19 21:31:13.253 (24656) info: cmd='connect' for 'Infrastructure' returned exception type='NewRelic::Agent::ForceDisconnectException' message='Legacy server agents are no longer supported'
2018-06-19 21:31:13.253 (24655) info: worker process exited with 1 - NOT restarting
```

* We removed the newrelic role in this PR

This may want newrelic-infrastructure, but I'll let the relevant team
decide.

A useful comment from last week that wasn't added to that merge

Setting up a jenkins worker docker image

* Revert "Removing the 403 for internal IP disclosure because it is breaking ecom (#4566)"

This reverts commit 6b817024.

* WIP

* cleanup

* WIP

Ikaspriskie/gocd dev environment

Initial commit for gocd dev environment

Revert "Initial support for journals service"